Falling Blocks are so laggy and glitched

Falling Blocks like sand,anvil etc are glitched when falling through height .

To reproduce -:

1)Place sand above two blocks or more .

2) Break bottom block at which sand block is placed on.(Remember that place sand so you can see  it falling.)

Observed results -:

1) Falling block are so laggy and buggy

Expected results-:

1) Falling block should fall as smooth as it was before.

Please watch attached file full.